You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Insights into Fern Evolution from Mapping Chloroplast Genomes
Linda A. Raubeson and Diana B. Stein
American Fern Journal
Vol. 85, No. 4, Use of Molecular Data in Evolutionary Studies of Pteridophytes (Oct. - Dec., 1995), pp. 193-204
Published by: American Fern Society
Stable URL: http://www.jstor.org/stable/1547809
Page Count: 12
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Within the leptosporangiate ferns, chloroplast DNA (cpDNA) structural mutations have been identified by physical mapping. Earlier work revealed that members of four disparate "higher" fern families all possess cpDNAs that share the same set of complex rearrangements in the inverted repeat. Osmunda cpDNA lacks these rearrangements. We have examined the chloroplast genomes of additional ferns and determined that Polypodium and the schizaeaceous ferns share the rearrangements previously found in Cyathea, Pteridium, Adiantum, and Polystichum. Two additional cpDNA structural types also have been identified. A partial duplication and relocation of the gene chlL usually occurs with the other gene rearrangements found in "higher" ferns but may be lacking in the heterosporous water fern, Marsilea. Also, a structural type lacking any of these complex rearrangements, but still different from Osmunda, occurs in Gleichenia cpDNA. The phylogenetic implications of these findings conflict, at least in part, with previously proposed evolutionary hypotheses.
American Fern Journal © 1995 American Fern Society